The polyether-ester amide elastomer is one of the most popular elastomer with high thermoplasticity performance. It is mainly applied in high quality exercising equipment, electrical appliances, and piping materials. Since the polyether-ester amide elastomer has good mechanical strength and stability in both high and low temperature, and good shape processing ability, it can be widely utilized in many fields.
The most commonly known conventional manufacturing process of the elastic fiber is the dry-type method of DuPont, which comprises the steps of: first, producing a composition of polyurethane (PU) elastomer; second, extruding the composition from a spinning orifice in liquid form; and third, removing solvent by blowing heated nitrogen to the liquid form composition to obtain the elastomer to form the elastic fiber. The volatilization of the solvent such as dimethyl formamide (DMF) or dimethyl acetamide (DMAC) renders a serious drawback of the above dry-type method because the volatilizing solvent is very hazardous to human health and generates a great pollution to the environment. The manufacturer must invest a huge sum of money to dispose the solvent waste; therefore the dry-type method unreasonably increases the production cost of the elastic fiber that adversely affects the marketing development and competition.
In recent years, Japan develops a new skill to manufacture elastic fiber from molten spin, such as Japanese manufacturers, Nisshinbo, Kancbo and Kuraray who invent to produce elastic fiber from molten spin of polyurethane (PU). Some other Japanese manufacturers such as Teijin and Unitika utilize molten spin of polyether-ester elastomer to produce elastic fiber. These Japanese methods are different from the above DuPont's method by eliminating the use of solvent, so that the manufacturing cost thereof is relatively lower than the DuPont's dry type method. However, the raw materials such as the polyurethane and polyether-ester have a relative low melting point, so that the physical properties of the polyurethane and polyether-ester will be damaged and deformed after heat treatment of the molten spin. Furthermore, the finished elastic fiber has to process further heat treatment, color dyeing and hydrolysis process, so that the elastic fiber produced by the molten spin method contains much more restraint in application and lower physical property than the elastic fiber made by the DuPont's dry-type method.